The letter "x" often represents a（n） （known） number in some Math exercises．
Can you tell me the （pronounce） of the word "agriculture"？
Sorry， I don't know， either．
Who gets up the （early） in your family？
My mum． She cooks breakfast for Dad and me．
You always look unhappy ！What （worry） you？
I really can't balance my study and hobbies．
The librarian was at me and seemed friendly． （smile）